Photoshop upgrade no longer possible

Adobe owns the code and that may, itself, be protected from copying, transferring, reselling, etc. but all owner's rights are not necessarily relinquished under the license agreement as I understand it. There have been court cases over the matter as it relates to software and, particularly when the license agreement is shrink-wrapped or "click-wrapped", some courts have held that the licensee is not bound by the terms of the agreement if it is only divulged after purchase. Other courts have taken the opposite position.

It is clear that you do not own Adobe's code and you may not mess with it. You may not offer it or its parts in any other form. But you do own the product you purchased. Some software companies have tried to dispute that -- some have won and some have lost. Some software companies play fast and loose under what they feel is the EULA umbrella.